FR2593234A1 - MULTI-CYLINDER INTERNAL COMBUSTION ENGINE WITH FUEL INJECTION, ESPECIALLY TURBO-COMPRESSOR ENGINE - Google Patents

Abstract

at. Multi-cylinder internal combustion engine with fuel injection, including turbo-compressor engine. b. Engine characterized in that, with the opening of the regulating valve 27, a part of the cylinders 11 to 14 is not ignited and that the remaining part of the cylinders 11 to 14, during the corresponding dosage of the quantity of fuel injected , is ignited at an extremely late instant, and that in the unlit cylinders 11 to 14 a total quantity of fuel is injected determining the additional volume of the exhaust gases. vs. The invention relates to internal combustion engines with several cylinders, with fuel injection, in particular engines with turbo-compressors. (CF DRAWING IN BOPI)

Description

1.- Multi-cylinder internal combustion engine with

  fuel injection, in particular a turbo engine

  compressor. "The invention starts from a combustion engine

  internal multi-cylinder with fuel injection

  including a compressor motor, with an air intake duct leading to the cylinders and comprising

  a throttle valve, with an exhaust gas channel

  from the cylinders, with a turbocharger which comprises a compressor arranged on the suction channel and a turbine driving the compressor disposed in the

  exhaust channel, and with a control valve

  in communication with the trunk

  the suction channel delimited by the compressor and the shut-off valve, a control valve which opens below a preset value derived from operating characteristics such as pressure or mass flow of air in the suction channel

  or the speed of rotation of the internal combustion engine

  dull or turbocharger, and which delivers air

  to obtain an additional volume of exhaust gas to the exhaust gas channel

the post-burner role.

  In such internal combustion engines 2.-

  equipped with a turbocharger, the energy of the exhaust gases

  is used to drive the turbine which, at its

  turn, drives the compressor to which it is connected, thanks to

  the supply pressure of the combustion air supplied to the cylinders is increased and thus the engine

  internal combustion develops a higher torque.

  For reduced mass flow rates in the cylinders, as is the case during operation

  accompanying or pushing the internal combustion engine

  dull used as engine of a motor vehicle or in low partial load, the mass flow of air

  produced by the turbo-compressor is however reduced.

  To increase this mass air flow, in a known turbocharger engine of the type initially mentioned, an additional volume of exhaust gas is generated

  in the exhaust duct bypassing the cy-

  linders, in the accompanying operation and in

  partial load operation, that is to say when

  that the throttle valve is not completely

  green, this additional volume of exhaust gas

  the turbine of the turbo-compressor and communicates

  when the speed of rotation is higher than that

  The amount of exhaust gas flowing out of the cylinders should be communicated to him alone. As a result, the turbo-compressor is maintained in rotational speed

  even in the functioning of accompaniment and

  ge, and delivers a sufficient mass flow of air

  health. The so-called "turbo-compressor hole" occurring in the case of turbo-compressor engines

  is avoided and in total the behavior of the turbo engine

compressor is improved.

  To obtain the additional volume of

  exhaust gas, the combustion air being under

  in the suction channel is brought, when the throttle valve is closed or partially

  open, to the exhaust gas channel through the

  of the control valve bypassing the cylinders

  ders. The amount of fuel required is fed into the exhaust gas channel via the cylinders whose ignition is switched off. The mixture of combustion air and unburned fuel comes on in the exhaust duct, thanks to which,

  gets the extra volume of exhaust gas

  dragging the turbine, As in this case, only quantities

  reduced fuel quantities are used, the injection

  of fuel in the cylinders does not need to be

  kill for each revolution of the crankshaft but can be performed only every m revolutions, m being an integer greater than or equal to J The internal combustion engine complies with

  the invention is then characterized in that, with

  of the regulating valve, part of the

  lindres is not lit and that the remaining part of the cylinders, at the corresponding dosage of the quantity

  injected fuel, is lit at an extreme moment

  In the unlit cylinders, a total quantity of fuel is injected which determines the additional volume of the exhaust gas. The internal combustion engine according to the invention with the characteristics defined above has the following characteristics: advantage that the internal combustion engine is not made more powerful by switching off all the ignition of the cylinders, but because

  only to be switched off

  some cylinders to reduce the mechanical work,

  Thus the transition to the functioning of accompanying

  is softened and the internal combustion engine

  rounder in the accompanying operation, Leins-

  If ignition is extremely late, then the performance of the cylinder operating at this time will be impaired, so that there is hardly any mechanical work and all of the combustion energy is used to raise, importantly, the temperature of the exhaust gas. The hot exhaust gases burn residue-free fuel-air mixture to the gas channel

  exhaust through the cylinders not

  and the regulating valve, thanks to which, the effi-

  the system is improved in relation to the produc-

  additional exhaust gas. The quantity of fuel necessary for the additional need of the exhaust gases is injected according to any distribution in the different unlit cylinders and

  arrives without being burned in the exhaust gas

  is lying. The regulating valve is opened as soon as

  their predefined derivative of the characteristic operating variables, such as the pressure or the mass flow rate of air in the suction channel, the rotational speed of the internal combustion engine, is crossed downwards and this valve supplies the channel of the exhaust gas with suction air that is under the pressure that prevails in the suction channel

  downstream of the throttle valve in the flow direction

  is lying. This preset value is set to

  that the situation described intervenes in the functioning

  in conjunction with the internal combustion engine (throttle valve) and / or in the operation at low partial load (valve very little open). This predefined value can also be formed by a logical combination of these characteristic quantities

Operating.

  Other features of the invention make it possible to envisage advantageous supplements and

  improvements of the internal combustion engine defined above.

  above. An advantageous embodiment of 5.-

  the invention is obtained in that for each nth program

  ignition, the lit part of the cylinders and the

  of the unlit cylinders is composed differently

  ferent from all cylinders, n being any integer. With these provisions, the part of the cylinders in operation, that is to say the lit cylinders, is distributed over the total number of existing cylinders. Each time at least one cylinder

  previously lit is not lit in the

  immediately following lumen, and a cylinder previously

  not lit is lit in this next program. It is obvious

  te as well as unequal temperatures of chambers of

  combustion are established in the cylinders, and in combination

  with an embodiment of the invention se-

  wherein the regulating valve is arranged in a bypass bridging the throttle valve, preventing

  that the different suction pipes to the cy-

  linders dry out, which would make it problematic to restore ignition of the mixture. We are in

  further assured that there is no fuel in the oil.

  An advantageous form of the invention is obtained in that the regulation valve is arranged

  in a bypass bridging the throttle valve.

  Thanks to the arrangement of the regulating valve ex-

  clusively on the fresh air side before the cylinders

  internal combustion engine, the cost of construction

  This control valve is significantly reduced because it does not have to be designed for very high load requirements, such as when, for example,

  according to the embodiment of the invention se-

  where the regulating valve is in communication

  the outlet side with the section of the exhaust gas

  When connected to the cylinders, this valve receives, at the outlet side, the hot exhaust gases in the exhaust gas channel. In addition, the 6.- lit cylinders are filled with air in a significantly more intense

  that this is not possible otherwise in operational

  companion, which again facilitates the alteration

desired performance.

  The invention will be explained in more detail

  in the description below with reference to the examples

  embodiment shown in the accompanying drawings, in which:

  - Figures 1 and 2 represent respectively

  schematically a turbo-compressor engine.

  The turbo-compressor motor sketched

  only schematically in Figure 1, as an example

  of a multi-cylinder internal combustion engine with fuel injection, comprises an engine block 10

  with four cylinders which are indicated on the engine block

  and designated by references 11 to 14. These

  11 to 14 are connected to a lightning installation.

  age 15 which, depending on the position of the town tree,

  brequin turns on, in every revolution of this tree of

  crankshaft, the cylinders 11 to 14.

  jection of fuel 16 brings to the different cylinders

  11 to 14 a quantity of metered fuel, which is injected

  in the cylinders 11 to 14 via injection valves, not shown. The motor unit 10 leads to a suction channel 17, which opens into

  suction pipes 171 to 174 leading to the different

  cylinders 11 to 14. These cylinders start from

  exhaust manifolds 181 to 184 which are assembled

  exhaust gas channel 18. A turbo-

  compressor 20 is constituted in a known manner, of a com-

  presser 21 and a turbine 22 connected to this compressor

  21 through a coupling shaft 23.

  As usual, the compressor 21 is disposed in the suction channel 17, while the turbine 22 is disposed in the exhaust gas channel 18. A 7.- valve 19 for regulating the supply pressure is connected upstream of the turbine 22 in the channel

  exhaust gas 18, valve through which the

  bit of the exhaust gases supplied to the turbine 22 as a function of

  at full load, can be tuned to the exhaust duct section 18 from the turbine

  22 opens into an exhaust pipe 24.

  In the suction channel 179, a throttle valve 25 which can be controlled, S is arranged upstream of the suction pipes 171 to 1749, this valve reducing the suction pressure P 1 prevailing in the suction channel. 17 at a pressure P22 in the suction pipeo Depending on the engine load, the throttle valve 25 releases a more or less large cross section of the suction channel 17 for the passage of the suction air, so that the P22 pressure in the suction pipe therefore takes different values. The throttle valve 25

  is bridged by a bypass 26 which opens on the one hand.

  in the section of the exhaust gas channel 18, de-

  limited by the throttle valve 25 and the compressor 21, and on the other hand, in the section of the exhaust gas channel 18 delimited by the throttle valve 25 and the various suction pipes 171 to 174e. In the branch 26, a control valve is arranged

  27 controlled pneumatically or electrically.

  This regulating valve 27 is constituted so

  that it is normally closed and that it is

  that the pressure p22 prevailing in the suction channel 17 downstream of the throttle valve 25, that is to say in the section of the suction channel 17 between the throttle valve 25 and the pipes of This preset value set is then set so that it is passed down by the pressure P22 in the operation 8.- in thrust or for a reduced partial load, c that is, when the throttle valve 25 is completely or almost completely closed. A control unit 28 connected to the control valve 27, the control valve 25, the ignition system 15 and the fuel injection device 15, influence

  the ignition of the various cylinders 11 to 14 and the injection

  fuel, as described below: If, while the throttle valve 25 is completely or almost completely closed,

  (functioning as an accompaniment or dependent

  reduced pressure), the pressure P22 upstream of the pipes

  171 to 174 is less than the predefined value

  finished, the regulating valve 27 opens. As a result, suction air arrives with the pressure P21 via the suction pipes 171 to 174 to the

  cylinders 11 to 14. Through the control unit

  During operation 28, during each ignition program, part of the cylinders 11 to 14, for example the cylinders 11 to 13, are not lit, and the remaining part of the cylinders 11 to 14, for example the cylinder 14, is lit only when at an extremely late moment. In the lit cylinder 14, a predetermined quantity of fuel is injected by the fuel injection device 16. As a result of the late ignition time, this quantity of fuel

  together with the suction air in the cylinder

  dre 14, with a bad return, as it results

  little mechanical work and extreme exhaust

  hot. In the remaining part of the unlit cylinders 11 to 14, that is to say in this case, the cylinders

  11 to 13, a total quantity of fuel is injected

  The unloaded air in the rolls 11 to 13 and the amount of unbridged fuel reach the gas channel 9. The amount of injection can then be different in the various cylinders 11 to 13.

  exhaust 18 oh they are lit by exhaust gases

  hot parts coming out of the cylinder 14 in operation.

  This results in an additional volume of exhaust gas

  feeds the turbine 22 and maintains the turbine

  ci, even in accompanying operation of the engine, at a speed of rotation large enough to ensure a sufficient supply pressure. This additional volume of exhaust gas can be metered very accurately by dosing the amount of fuel injected into the unlit cylinders, in this case

the cylinders 11 to 13.

  To avoid uneven temperatures

  combustion chambers and desiccation of

  suction bulbs 171 to 174, the part of the cylinders

  switched on and the part of the cylinders not lit, is

  posed differently from all the cylinders 11 to 14 at each nth ignition program, n then being any integer, for example 1

  This means that during a first program of

  mage, that is to say during a revolution of the crankshaft, the cylinder 14 is lit and the cylinders 1i to 13 are not lit, and that during the following ignition program, the cylinder 11 is on and the

  cylinders 12 to 14 are not lit, and so on.

  In this way, so to speak, the cylinder in operation

  circulation. Of course, two cylinders can also be lit at each ignition program, and two cylinders can not be ignited. The turbo-compressor motor shown diagrammatically in FIG.

  little of the turbo-compressor cylinder sketched on the

  1 and previously described, so that the same

  component parts are assigned the same references.

  The only difference is that the bypass 26 'not only bridges the throttle valve 25, but 10.- the series connection of the throttle valve 25 and the engine block 10, and thus opens into the channel of the valves. exhaust gas 18 and in fact in the section of this exhaust gas channel delimited by the engine block 10 and the valve 19 for regulating the supply pressure. With this arrangement, when the valve

  27 is open, the air sucked in with the pressure

  P21 arrives directly bypassing the engine block in the exhaust channel 18. The corresponding quantity of fuel is supplied via

  unlit cylinders in the exhaust gas channel.

  18. As in Figure 1, an additional volume of

  exhaust gas for the training of the com-

  pressure 22 is obtained in the exhaust gas channel.

  now playing the role of post-burner

  combustion of the fuel-air mixture forming in this channel.

  The ignition of the various cylinders 11 to 14 and the injection

  fuel in the different cylinders 11 to 14 are performed in the same way as described

about Figure 1.

  The invention is not limited to the previously described embodiments. This is how the control valve can be opened not only depending on the pressure in the suction channel,

  but also according to other quantities characteristic

  functioning, such as mass flow

  air in the suction channel or the speed of

  turbo-compressor or turbo-engine

  compressor itself. It is also possible to obtain

  the preset value for which the regulating valve

  opens, through a combination of

  of all these operating characteristic quantities or of a part of them, such as the pressure and the mass flow rate of the air in the suction channel and the speed of rotation of the engine.

  turbo-compressetur and turbo-compressor him = same.

  The invention can be applied of the same

  to an internal combustion engine or to a

  i: turbo-coprocessor which comprises several turbochargers

  compressors, in which case a turbo-compressor supplies respectively a group of several cylinders 12.-

RE V E N D I C A T I ONS

  1.- Multi-cylinder internal combustion engine with fuel injection, in particular a compressor engine, with an air suction channel terminating in the cylinders and having a throttle valve, with a gas channel exhaust from

  cylinders, with a turbocharger that includes a

  presser disposed on the suction channel and a turbine driving this compressor arranged in the gas channel

  exhaust system, and with a regulating valve is

  on the entry side with the section of the

  nal suction defined by the compressor and the valve

  throttling valve, regulating valve which opens

  below a predefined value derived from

  operating characteristics such as the pressure or the mass flow of air in the suction channel

  or the speed of rotation of the internal combustion engine

  or a turbocharger, and which delivers combustion air to obtain an additional volume of exhaust gas to the exhaust gas channel acting as a post-burner, an internal combustion engine characterized in that, with the the opening of the regulating valve (27) a part of the cylinders (11 to 14) is not lit and the remaining part of the cylinders (11 to 14)

  14) when the corresponding quantity of fuel is

  injected, is switched on at an extremely

  dif, and that in the unlit cylinders 411 to 14) it

  a total quantity of fuel is injected

  the additional volume of the exhaust gas.

  2.- internal combustion engine according to claim 1, characterized in that for each nth ignition program, the portion of the cylinders on and the part of the unlit cylinders (11 to 14) is composed differently from the all cylinders

  (11 to 14), n being any integer.

  15.- 3.- Internal combustion engine according to one of

  any of claims 1 or 2, characterized in that

  the control valve (27) is in communication with the exhaust duct section (18) connected to the cylinders (11 to 14). 4.- Internal combustion engine according to one

  any of claims 1 or 2, characterized in that

  the regulating valve (27) is disposed in a bypass (26) flanking the throttle valve (25)